A. Field of the Invention
The present invention relates to device for preventing pipes and other liquid carriers from freezing.
B. Description of the Prior Art
The number two cause of property damage is water damage. Freezing pipes cause a disproportionate amount of preventable water damage, when simple circulation of the water could elevate the temperature in the pipe sufficient to prevent freezing of the pipes.
Regulations require that water mains and other underground runs of water pipes be maintained a certain distance below the surface. In addition to the obvious protection provided to the pipes from digging, roots and other potential physical damage, the natural insulation and heating of the ground below the surface can ensure that the water in the pipes can not freeze. Simple calculations provide that running the pipes 24–36 inches below the surface, depending on how far or north the locale is, will maintain the water lines at or above approximately 50 degrees.
However, once the pipe is brought to the surface to connect to a house or piping within a house or other structure, the pipe is not longer insulated by the ground. In inclement weather, this piping can freeze. The expansion of the ice within the pipes can cause the pipes to burst resulting in immediate water damage or damage after the water thaws. Typically this temperature drop can be avoided by either adequate interior heating keeping the pipes and the liquid therein warm. The temperature drop can also be avoided by using the water lines, which causes a constant introduction of city water at 50 degrees from the water main, or hot water from the hot water heater, in the cold water and hot water supplies, respectively.
This damage can be severe, especially considering that one of the hardest hit properties by water damage is vacation houses or other sparingly used structures. Owners often turn off the interior heating and shut off the hot water heater, subjecting the interior hot water and cold water supply pipes to potentially sub-freezing temperatures. Since the house sits in disuse, the water is not circulated. If freezing temperatures exist outside the pipes, the liquid inside the pipe will soon freeze. And once the pipes burst under the force of the ice inside the pipes, large quantities of water may leak before the owner returns to discover the leak.
One prior art device that has been used in the past on exterior faucets is a drip sleeve. A sleeve having a threaded receiver is installed on a faucet. An internal throat allows water to pass unrestricted therethrough when the faucet is turned on. The sleeve has threads at a second end so that a garden hose or such can be threaded thereto such that the faucet can operate normally as if the sleeve were not in installed. During cold weather, the sleeve can be rotated to allow a limited amount of constant flow (“drip”) to provide water constantly flowing through the pipe to constantly introduce 50 degree city water through the pipe to maintain above freezing water temperatures in the pipes. Additionally, the effect of constantly flowing water is also known to inhibit the production of ice. However, this device has the drawback that a large quantity of water will flow through the sleeve while in operation, and the flow is not a function of the water temperature so may flow be completely unnecessary for the protection of the pipes.
The current invention provides a simple temperature release valve that allows only a discrete amount of water to flow to drain (or to waste) sufficient to raise the temperature of the water in the pipes to prevent freezing. None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.